Seismo-stratigraphic characters of paleocontourites along the Calabro-Tyrrhenian margin (Southern Tyrrhenian Sea)

Abstract: Buried contourites located offshore Capo Suvero (Calabria, Southern Italy) have been investigated using analysis of Sparker profiles. The deposits onlap an erosional surface produced by a slide in the upper slope Pleistocene units. The overall seismic characters of the deposits suggest an interpretation as infilling drift deposits formed by the activity of a northward bottom-current flowing along the paleoslope. The deposits, with thickness up to ~140 m, are made up of 3 units, including 8 sub-units with an upward-convex shape on dip profile and a lenticular shape on strike profile. The stacking pattern of sub-units highlights a general upslope migration, interrupted by two downslope shifts accompanied by erosion; a general migration toward the north has also been recognized. This evolution could be explained by autocyclic processes, due to the seafloor modification during the growth of the deposits; otherwise it could also be related to variations of the oceanographic conditions or eventually to sea-level changes. Formation of the deposits (located in the present-day 110–240 m bathymetric range) could have been significantly deeper than present location as a consequence of the regional uplift affecting the area since Pleistocene. Under this hypothesis, an intermediate current may be inferred for the formation of the deposits. These deposits are quite rare along the Tyrrhenian margins and their formation–preservation seems to be related to the peculiar morphological setting of the area, characterized by a morpho-structural high and a slide scar. Their presence is relevant for the stratigraphy of the eastern Tyrrhenian margin as they underline the importance of bottom-current processes, with implications on paleocirculation reconstructions of the Mediterranean Basin. [Copyright &y& Elsevier]